With development of science and technology, smart phones have become essential goods of life. User can call, chat and/or browse the Web via the smart phone. However, smart phones are using virtual keyboards currently. The virtual keyboards are always occupy parts of the phone screens. Each virtual key is basically accounted for a total of three or four-letters key. User cannot enter quickly using the virtual keyboard. Further, the gap between the virtual keys is very small, which causes to misuse easily.